equation

Now... I am sure that solutioin is not defined for a=0, but can I reduce the fraction to:,
without any notes, or do I have to state that reduction of fraction is only posible for not equal 3? Or in other words, is a=3 also a solution?

Now... I am sure that solutioin is not defined for a=0, but can I reduce the fraction to:,
without any notes, or do I have to state that reduction of fraction is only posible for not equal 3? Or in other words, is a=3 also a solution?

Look at the original equation, you will see that it is inconsistent when a=3.
So you know that if there is a solution a!=3, and you can do the cancellation.
But you should say so.